For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningLuggage Compartment Description and Operation
Rear Compartment Lid Release System Components
Body control module (BCM)
Exterior rear compartment lid release switch
Rear compartment lid release actuator
Rear compartment lid release relay
Rear Compartment Lid Release Operation
When the exterior rear compartment lid release switch is ...
Rear Side Door Check Replacement
Preliminary Procedure
Remove rear side door trim panel. Refer to Rear Side Door
Trim Replacement
Remove the rear side door water deflector. Refer to Rear Side Door Water
Deflector Replacement
Rear Side Door Check Bolt
Caution: Refer to Fastener Caution in the Pre ...
Driver or Passenger Seat Retractor Side Belt Replacement
Warning: Refer to SIR Warning in the Preface section.
Warning: In order to prevent accidental deployment and the risk of personal
injury, do not dispose of an undeployed inflatable
restraint seat belt pretensioner as normal shop waste. Undeployed seat belt
pretensioners contain substance ...